低压氮化镓器件谐振驱动技术及其反向导通特性

Resonant Drive Technology and Reverse Conduction Characteristics of Low Voltage GaN Devices

继硅(Si)和砷化镓(GaAs)之后,半导体材料出现了第三代以氮化镓(GaN)为代表的宽禁带半导体材料,其特点包括临界击穿电场高、饱和电子速度高、电子密度高、电子迁移率高及导热率高等,是一种适用于高频、高压、高温、大功率的抗辐射等级高的半导体材料。由于GaN器件的开关特性、驱动技术及损耗机制相比Si MOSFET有显著差异,如何实现合理的驱动,对发挥其优势至关重要。以同步Buck变换器为例提出一种谐振驱动技术,并给续流管栅极加一偏置电压,以减小反向压降、提高效率。实验结果表明,此谐振驱动技术可有效提高驱动的可靠性,加载偏置电压后变换器的效率也可得到有效提高。

After silicon (Si) and gallium arsenide (GaAs), semiconductor material has third generation of wide band gap semiconductor materials represented by gallium nitride (GaN). Its characteristics include high critical breakdown electric field, high saturation electron speed, high electron density, high electron mobility and high thermal conductivity. It is suitable for high frequency, high pressure and high temperature, high power semiconductor materials with high radiation resistance. Because the switching characteristics, driving technology and loss mechanism of GaN devices have significant differences compared with the Si MOSFET, how to realize the rational drive method is very important to achieve its advantages. Taking a synchronous buck converter as an example, a resonant driving technique was proposed, and a bias voltage was added to the gate of the rectifier transistor to reduce the reverse voltage drop and improve the efficiency. The experimental results show that the resonant drive technology can effectively improve the reliability of the drive, and the efficiency of the converter can also be effectively improved after adding the bias voltage.